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M Nair R Arora J C Mohan G S Kalra K K Sethi M Nigam M Khalilullah 《International journal of cardiology》1991,32(3):389-394
Cross-sectional and Doppler echocardiography are currently the most important non-invasive tests for the evaluation of mitral stenosis. Recent experience has, however, shown that parameters that are reliable before mitral valvotomy may not be valid after the procedure. We have studied the validity of estimation of the area of the mitral valve by echo-planimetry, by Doppler pressure half time and the transmitral end-diastolic pressure gradient calculated by continuous wave Doppler in 100 patients (aged 10-30 years) before and after balloon mitral valvoplasty (n = 70) or surgical closed mitral valvotomy (n = 30). These patients underwent cardiac catheterisation and echocardiographic studies before, immediately after and 8-12 (9.3 +/- 2.2) weeks following balloon valvoplasty or closed valvotomy. The area as estimated echocardiographically correlated well with that obtained by the Gorlin formula before (r = 0.80), but not immediately after (r = 0.67) or on follow up after mitral valvotomy. There was good correlation between Doppler pressure half time and the area as estimated by the Gorlin formula before (r = 0.89) and on follow up after valvotomy (r = 0.82), but the correlation was not as good in the immediate period after valvotomy (r = 0.60). The end-diastolic pressure gradients obtained by Doppler examination and at cardiac catheterisation correlated well with each other before (r = 0.94), immediately after valvotomy (r = 0.92) and on follow up (r = 0.94). Hence, the reliability of estimation of the area of the mitral valve by echo-planimetry and by Doppler pressure half time varies according to the time at which the examination is performed following commissurotomy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
64.
Pharmacological Treatment of Dysphagia in Stroke 总被引:10,自引:0,他引:10
The pharynx is important for a normal swallow and it has been suggested that pharmacological agents may play a role in the
management of pharyngeal dysphagia, but none have been formally evaluated. A pilot double-blind, placebo-controlled study
was undertaken in 17 hospitalized patients with persistent dysphagia 2 weeks after stroke. Patients were randomized to treatment
with slow-release nifedipine 30 mg orally (n = 8) or placebo (n = 9) following specialist swallowing assessment and videofluoroscopy
to exclude severe dysphagia. Videofluoroscopy was repeated after 4 weeks of treatment. Fourteen patients (active 6, placebo
8) completed the study. Two patients died (active 1, placebo 1) and 1 patient in the active group had to be withdrawn because
of progressive heart failure. Initial assessment showed impairment in the pharyngeal phase with delayed triggering of swallow,
poor laryngeal elevation, and prolonged pharyngeal transit times in all patients. Silent aspiration was seen in 4 patients
(active 2, placebo 2). Improvement in swallowing was seen in 8 patients (active 5, placebo 3) at the end of 4 weeks. There
were significant changes in the pharyngeal transit time (mean −1.34 second; 95% C.I. −2.56, −0.11) and swallow delay (mean
−1.91 seconds; 95% C.I. −3.58, −0.24) in the active group suggesting improvement in the initiation of pharyngeal contractions
and reduction in the time taken for the bolus to transverse the pharynx. A similar change was not seen in the placebo group.
It is suggested that pharmacological agents such as nifedipine may have a role in the management of stroke-related dysphagia
and merit further investigation. 相似文献
65.
BACKGROUND: an organized, goal-defined and time-specified plan of management as envisaged by the integrated care pathway approach can achieve quality outcomes at lower cost. Integrated care pathways may have applications to stroke management because diagnosis is well defined, complex interdisciplinary inputs are required and there is good evidence on best practice. METHOD: we reviewed medical, nursing, rehabilitation and health services databases to identify studies on integrated care pathways in stroke management. Criteria for inclusion were: use of a care pathway or similar methods in acute or rehabilitation settings, randomized studies or non-randomized comparisons with concurrent or historical controls and some form of outcome assessment. RESULTS: we identified six non-randomized studies of acute stroke. One used concurrent controls; the rest used historical controls. Only one study investigated stroke rehabilitation and this used a quasi-randomized controlled design. Five studies in the acute setting demonstrated reduced hospital stay. A reduction in costs of care was reported in all five studies that examined costs. Two studies reported improved uptake of medical interventions. No difference in length of hospital stay, costs or functional status was seen in the rehabilitation study. CONCLUSIONS: integrated care pathway methodology may facilitate quality and cost improvements in stroke care, but evidence is weak and uncertainty exists. Further evidence is needed before implementation in practice. 相似文献
66.
Georgia M. Davis Eileen Faulds Tara Walker Debbie Vigliotti Marina Rabinovich Joi Hester Limin Peng Barbara McLean Patricia Hannon Norma Poindexter Petrena Saunders Citlalli Perez-Guzman Seema S. Tekwani Greg S. Martin Guillermo Umpierrez Shivani Agarwal Kathleen Dungan Francisco J. Pasquel 《Diabetes care》2021,44(4):1055
OBJECTIVEThe use of remote real-time continuous glucose monitoring (CGM) in the hospital has rapidly emerged to preserve personal protective equipment and reduce potential exposures during coronavirus disease 2019 (COVID-19).RESEARCH DESIGN AND METHODSWe linked a hybrid CGM and point-of-care (POC) glucose testing protocol to a computerized decision support system for continuous insulin infusion and integrated a validation system for sensor glucose values into the electronic health record. We report our proof-of-concept experience in a COVID-19 intensive care unit.RESULTSAll nine patients required mechanical ventilation and corticosteroids. During the protocol, 75.7% of sensor values were within 20% of the reference POC glucose with an associated average reduction in POC of 63%. Mean time in range (70–180 mg/dL) was 71.4 ± 13.9%. Sensor accuracy was impacted by mechanical interferences in four patients.CONCLUSIONSA hybrid protocol integrating real-time CGM and POC is helpful for managing critically ill patients with COVID-19 requiring insulin infusion. 相似文献
67.
Seema Shrivastava Liang Ma El‐Li Tham John H. McVey Daxin Chen Anthony Dorling 《Immunology》2013,139(2):219-226
The precise function of tissue factor (TF) expressed by dendritic cells (DC) is uncertain. As well as initiating thrombin generation it can signal through protease‐activated receptor 2 (PAR‐2) when complexed with factor VIIa. We investigated the expression and function of TF on mouse bone marrow (BM) ‐derived DC; 20% of BM‐derived DC expressed TF, which did not vary after incubation with lipopolysaccharide (LPS) or dexamethasone (DEX). However, the pro‐coagulant activity of DEX‐treated DC in recalcified plasma was 30‐fold less than LPS‐treated DC. In antigen‐specific and allogeneic T‐cell culture experiments, the TF on DEX‐treated DC provided a signal through PAR‐2, which contributed to the reduced ability of these cells to stimulate CD4+ T‐cell proliferation and cytokine production. In vivo, an inhibitory anti‐TF antibody and a PAR‐2 antagonist enhanced antigen‐specific priming in two models where antigen was given without adjuvant, with an effect approximately 50% that seen with LPS, suggesting that a similar mechanism was operational physiologically. These data suggest a novel TF and PAR‐2‐dependent mechanism on DEX‐DC in vitro and unprimed DC in vivo that contributes to the low immunogenicity of these cells. Targeting this pathway has the potential to influence antigen‐specific CD4+ T‐cell activation. 相似文献
68.
Purpose
The aim of the study was to assess the distribution of accessory foramina in the mandibular body with computed tomography (CT).Materials and methods
The CT images of the mandibular body in 300 subjects (183 females and 117 males aged between 12 and 85 years) were retrospectively analysed for the presence of accessory foramina. The buccal and lingual surfaces were examined by dividing them into anterior and posterior quadrants.Results
Of the 300 subjects, 26 presented with accessory foramina on buccal posterior aspect and 70 subjects presented on buccal anterior aspect. Further, on the lingual posterior aspect, 132 subjects presented with accessory foramina and 59 subjects presented on lingual anterior aspect. Most of the subjects with accessory foramina in the buccal posterior, buccal anterior and lingual anterior regions had accessory foramina on other aspects of the mandible as well.Conclusion
A substantial number of subjects presented with accessory foramina on the lingual posterior aspect when compared to other aspects. Nevertheless, the number of subjects with accessory foramina on other aspects of the mandible was considerable and cannot be ignored. It is suggested that when an accessory foramen is identified in an individual on a particular aspect of the mandibular body, it is highly probable that he will exhibit accessory foramina on other aspects as well. 相似文献69.
70.
Chenji Sneha Ishaque Abdullah Mah Dennell Fujiwara Esther Beaulieu Christian Seres Peter Graham Simon J. Frayne Richard Zinman Lorne Genge Angela Korngut Lawrence Johnston Wendy Kalra Sanjay 《Brain imaging and behavior》2021,15(3):1641-1654
Brain Imaging and Behavior - Cognitive impairment is now recognized in a subset of patients with amyotrophic lateral sclerosis (ALS). The objective of the study was to identify group differences... 相似文献